Add Billet entity, BilletDesign, ticket designer, CRUD billets, commissions

- Create Billet entity: name, position, priceHT, quantity (nullable=unlimited),
  isGeneratedBillet, hasDefinedExit, notBuyable, type (billet/reservation_brocante/vote),
  stripeProductId, description, picture (VichUploader), category (ManyToOne CASCADE)
- Create BilletDesign entity (OneToOne Event): accentColor, invitationTitle, invitationColor
- Billet CRUD: add/edit/delete with access control, Stripe product sync on connected account
- Billet reorder: drag & drop with position field, refactored sortable.js for both categories and billets
- Ticket designer tab (custom offer only): accent color, invitation title/color, live iframe preview
- A4 ticket preview: 4 zones (HG infos+billet, HD affiche, BG association, BD sortie+invitation), fake QR code SVG
- Commission calculator JS: live breakdown of E-Ticket fee, Stripe fee (1.5%+0.25EUR), net amount
- Sales recap on categories tab: qty sold, total HT, total commissions, total net
- DisableProfilerSubscriber: disable web profiler toolbar on preview iframe
- CSP: allow self in frame-src and frame-ancestors for preview iframe
- Flysystem: dedicated billets.storage for billet images
- Upload accept restricted to png/jpeg/webp/gif (no HEIC)
- Makefile: add force_sql_dev command
- CLAUDE.md: add rule to never modify existing migrations
- Consolidate all migrations into single Version20260321111125
- Tests: BilletTest (20), BilletDesignTest (6), DisableProfilerSubscriberTest (5),
  billet-designer.test.js (7), commission-calculator.test.js (7),
  AccountControllerTest billet CRUD tests (11)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Makefile

@@ -75,6 +75,9 @@ migration_dev: ## Genere une migration via Docker dev
 migrate_dev: ## Execute les migrations via Docker dev
 	docker compose -f docker-compose-dev.yml exec php php bin/console doctrine:migrations:migrate --no-interaction
 
+force_sql_dev: ## Force la mise a jour du schema de la base de donnees dev
+	docker compose -f docker-compose-dev.yml exec php php bin/console doctrine:schema:update --force
+
 migrate_prod: ## Execute les migrations en prod via Docker
 	docker compose -f docker-compose-prod.yml exec php php bin/console doctrine:migrations:migrate --no-interaction --env=prod